TWI694267B - Optical lens - Google Patents

Abstract

An optical lens of the present disclosure assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, an optical filter and a sensor. The optical lens also has an axis. The first lens element, the fourth lens element and the sixth lens element have negative power, the second lens element, the third lens element and the fifth lens element have positive power.

Description

Optical lens

The invention relates to a lens, in particular to an optical lens.

In recent years, with the rapid development of portable electronic products, most electronic products, such as mobile phones, cameras, surveillance, etc. have built-in cameras to achieve the camera function. In this way, the application of optical lenses in electronic products is becoming more and more extensive.

In the camera, the camera captures the object by capturing visible light and finally makes the object image on the film or screen. Generally speaking, the larger the field angle of the lens in the camera, the more objects can be photographed, so that the wide-angle lens is more widely used.

Further, in the camera, the camera captures the object by acquiring visible light and finally causes the object to be imaged on the film or the screen. The optical lens directly affects the quality of the imaging quality and the quality of the imaging effect. In the prior art, optical lenses are mainly dominated by CCD and CMOS photosensitive elements and are increasingly miniaturized. However, after the existing optical lenses are gradually miniaturized, the angle of view of the optical lens is small, which limits the range of image capture, and Problems such as chromatic aberration make the final imaging quality of the optical lens poor.

In view of this, the present invention provides an optical lens with a small size and high imaging quality.

An optical lens has an optical axis. The optical lens includes a first lens element, a second lens element, a third lens element, and a A four-lens element, a fifth lens element, a sixth lens element, and an image plane, the first lens element has a first surface and a second surface, the second lens element has a third surface and a fourth surface, the first The three lens element has a fifth surface and a sixth surface, the fourth lens element has a seventh surface and an eighth surface, the fifth lens element has a ninth surface and a tenth surface, and the sixth lens element has a The eleventh surface and the twelfth surface further include an aperture located on the optical axis and disposed between the second lens element and the third lens element. The optical lens satisfies the following relationship: 0< T45<0.1; 0<T45M<0.2; where T45 is the horizontal distance between the center of the eighth surface and the intersection of the ninth surface and the optical axis, and T45M is the eighth surface and the The maximum value of the leveling distance between the ninth surfaces.

Further, it further includes a filter between the sixth lens element and the image plane and spaced apart, the filter having a front surface and a rear surface opposite to the front surface.

Further, the first surface is a convex curved surface extending toward the object side, the middle of the second surface is a concave curved surface toward the image side, the periphery of the second surface is flat, and the third surface is toward the object Square concave surface, the fourth surface is a convex curved surface toward the image side, the fifth surface is a convex curved surface toward the object side, the sixth surface is a convex curved surface toward the image side, and the seventh surface is Is a concave curved surface toward the object side, the eighth surface faces a concave curved surface on the image side, the edge of the ninth surface is a plane, the middle of the ninth surface faces a convex curved surface on the object side, and the tenth surface is toward the image A square convex curved surface, the eleventh surface is a concave curved surface toward the object side, and the middle of the twelfth surface is a concave curved surface toward the image side.

Further, the first lens element, the fourth lens element and the sixth lens element all have negative refractive power, and the second lens element, the third lens element and the fifth lens element all have positive refractive power .

Further, the optical lens further satisfies the following relationships: 1.02<N4/N5<1.58, 0.28<V4/V5<0.85, where N4 and N5 are the refractive index of the fourth lens element and the fifth lens element, V4 and V5 are Abbe numbers of the fourth lens element and the fifth lens element, respectively.

Further, the optical lens further satisfies the following relationship: 0.77<f1/(f4*f5)<2.75, where F1 is the focal length of the first lens element, F4 is the focal length of the fourth lens element, and F5 is The focal length of the fifth lens element.

Further, the optical lens further satisfies the following relationship: 1.12<TTL/IMH<3.05, 90°<2ω<150°, where TTL is between the first surface of the first lens element and the image plane The horizontal distance, IMH is the diameter of the largest imaging circle of the optical lens, and ω is the half angle of view.

Further, the optical lens further satisfies the following relationship: 0.35<D1/(R1*R2)<16.31, where D1 is the aperture of the first lens element, R1 is the radius of curvature of the first surface, and R2 is The radius of curvature of the second surface.

Further, the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element are all arranged axisymmetrically with respect to the optical axis.

The optical lens of the present invention can reduce the overall size of the optical lens while improving the imaging quality.

10: First lens element

101: first surface

102: second surface

20: Second lens element

201: third surface

202: fourth surface

30: third lens element

301: Fifth surface

302: Sixth surface

40: fourth lens element

401: Seventh surface

402: Eighth surface

50: fifth lens element

501: Ninth surface

502: Tenth surface

60: sixth lens element

601: Eleventh surface

602: Twelfth surface

70: filter

80: like plane

100: optical lens

110: optical axis

120: Aperture

FIG. 1 is a schematic structural diagram of the optical lens of the present invention.

FIG. 2 is a graph showing the longitudinal distribution characteristic region of the spherical aberration of visible light imaging of the optical lens in the first embodiment of the present invention.

FIG. 3 is a lateral distribution curve of the imaging chromatic aberration of visible light of the optical lens in the first embodiment of the present invention.

4 is a graph showing the imaging field curvature characteristics of the optical lens to visible light in the first embodiment of the present invention.

FIG. 5 is a graph showing the distortion characteristic of the optical lens imaging visible light in the first embodiment of the present invention.

6 is a graph showing the longitudinal distribution characteristic of spherical aberration of the optical lens imaging visible light in the second embodiment of the present invention.

FIG. 7 is a lateral distribution characteristic curve diagram of chromatic aberration of the optical lens imaging visible light in the second embodiment of the present invention.

FIG. 8 is a graph showing the characteristics of the field area of the optical lens imaging visible light in the second embodiment of the present invention.

9 is a graph showing the distortion characteristic of the optical lens imaging visible light in the second embodiment of the present invention.

As shown in FIG. 1, the optical lens 100 in the embodiment of the present invention includes a first lens element 10, a second lens element 20, a third lens element 30, and a fourth lens element arranged in this order from the object side toward the image side 40. The fifth lens element 50 and the sixth lens element 60, the filter 70, and the image plane 80.

The optical lens 100 has an optical axis 110. The first lens element 10, the second lens element 20, the third lens element 30, the fourth lens element 40, the fifth lens element 50, and the sixth lens element 60 are all arranged axisymmetrically with respect to the optical axis 110 .

The first lens element 10 has a negative refractive power, and has a first surface 101 and a second surface 102. The first surface 101 is a convex curved surface protruding toward the object side. The middle of the second surface 102 is a concave curved surface toward the image side, and the periphery of the second surface 102 is flat.

The second lens element 20 has a positive refractive power. The second lens element 20 has a third surface 201 and a fourth surface 202. The third surface 201 is a concave curved surface toward the object side. The fourth surface 202 is a convex curved surface toward the image side.

The third lens element 30 has a positive refractive power. The third lens element 30 has a fifth surface 301 and a sixth surface 302. The fifth surface 301 is a convex curved surface toward the object side. The sixth surface 302 is a convex curved surface toward the image side.

An aperture 120 is further provided between the second lens element 20 and the third lens element 30. The diaphragm 120 is located on the optical axis 110 and disposed near the fifth surface 301 of the third lens element 30.

The fourth lens element 40 has negative refractive power. The fourth lens element 40 has a seventh surface 401 and an eighth surface 402. The seventh surface 401 is a concave curved surface toward the object side. The eighth surface 402 is a concave curved surface toward the image side.

The fifth lens element 50 has positive refractive power. The fifth lens element 50 has a ninth surface 501 and a tenth surface 502. The edge of the ninth surface 501 is a flat surface, and the middle of the ninth surface 501 is a convex curved surface toward the object side. The tenth surface 502 is a convex curved surface facing the image side.

The sixth lens element 60 has negative refractive power. The sixth lens element 60 has an eleventh surface 601 and a twelfth surface 602. The eleventh surface 601 is a concave curved surface toward the object side. The middle of the twelfth surface 602 faces a concave curved surface on the image side.

The filter 70 is used to filter the infrared light in the light passing through the sixth lens element 60, so as to avoid the imaging quality of the object on the image plane 80. The filter 70 has a front surface 71 and a rear surface 72 opposite to the front surface.

The image plane 80 is used for imaging. Light rays pass through the first lens element 10, the second lens element 20, the third lens element 30, the fourth lens element 40, the fifth lens element 50, the sixth lens element 60, and the filter from the object side The sheet 70 is then imaged on the image plane 80.

In the present invention, the first surfaces of the first lens element 10, the second lens element 20, the third lens element 30, the fourth lens element 40, the fifth lens element 50, and the sixth lens element 60 101, second surface 102, third surface 201, fourth surface 202, fifth surface 301, sixth surface 302, seventh surface 401, eighth surface 402, ninth surface 501, tenth surface 502, eleventh The surface 601 and the twelfth surface 602 both satisfy the following aspheric formula:

Where z is the displacement value from the optical axis with the surface vertex as the reference at the height h along the optical axis, c is the reciprocal of the radius of curvature, h is the radius of the lens from the optical axis 110, and K is the fixed number of the cone ( Coin Constant), Ai is the i-th order Aspherical Coefficient (i-th order Aspherical Coefficient). Σ A _i h ⁱ means accumulating A _h ⁱ , i is a natural number.

Further, the optical lens of the present invention satisfies the following relationships: 0<T45<0.1 (1); 0<T45M<0.2 (2); 1.02<N4/N5<1.58 (3); 0.28<V4/V5<0.85 ( 4); 0.77<f1/(f4*f5)<2.75 (5); 1.12<TTL/IMH<3.05 (6); 90°<2ω<150° (7); 0.35<D1/(R1*R2)< 16.31 (8)

Where, T45 is the horizontal distance between the center of the eighth surface 402 and the intersection of the ninth surface 501 and the optical axis 110, respectively. T45M is the maximum leveling distance between the eighth surface 402 and the ninth surface 501. N4 and N5 are the refractive indexes of the fourth lens element 40 and the fifth lens element 50, respectively. V4 and V5 are the fourth lens element 40 and the fifth lens element 50 Shellfish. F1 is the focal length of the first lens element 10. F4 is the focal length of the fourth lens element 40. F5 is the focal length of the fifth lens element 50. TTL is the horizontal distance between the first surface 101 of the first lens element 10 and the image plane 80. IMH is the diameter of the largest imaging circle of the optical lens. D1 is the aperture of the first lens element 10. R1 is the radius of curvature of the first surface 101. R2 is the radius of curvature of the second surface. ω is the half angle of view.

Further, the optical lens satisfies the relational expressions (1)-(4), so that the chromatic aberration of the optical lens can be reduced, and at the same time, the imaging quality of the optical lens can be improved with a large angle of view.

Further, by satisfying the above relationship (5), it is used to balance the refractive powers of the first lens element 10, the fourth lens element 40, and the fifth lens element 50, thereby improving the sensitivity of the imaging tolerance of the optical lens.

Further, the ratio of the length of the optical lens to the largest imaging circle is defined by satisfying the above relationship (6).

Further, the angle of view of the optical lens is defined by satisfying the above relationship (7).

Further, the ratio of the diameter of the first lens element 10 to the radius of curvature is defined by satisfying the above relationship (8), thereby miniaturizing the size of the optical lens.

The optical lens of the present invention will be further described as follows through different embodiments:

Example one:

Table 1-2 below shows some parameters of the optical lens described in the first embodiment of the present invention. In Table 1, where R represents the radius of curvature of the corresponding surface, L represents the separation distance between two adjacent surfaces on the optical axis 110, N represents the refractive index of each surface, Vd represents the Abbe number, and K represents the conic constant .

The first lens element 10, the second lens element 20, and the third lens element 30 in the optical lens in the first embodiment of the present invention can be obtained by satisfying the above formula (a) in Table 1-2. , The fourth lens element 40, the fifth lens element 50 and the sixth lens element 60 correspond to the first surface 101, the second surface 102, the third surface 201, the fourth surface 202, the fifth surface 301, the third The six surfaces 302, the seventh surface 401, the eighth surface 402, the ninth surface 501, the tenth surface 502, the eleventh surface 601, and the twelfth surface 602 are aspherical.

Table 2

Further, according to the data in Table 1-2, the optical lens according to the first embodiment of the present invention satisfies the following relationship: EFL=0.79; F=2.4; 2ω=112.1°; TTL=3.41; IMH=2.163; T45=0.03 ; T45M=0.05; N4/N5=1.06; V4/V5=0.40; f1/(14*f5)=1.25; D1/(R1*R2)=2.92.

Further, FIG. 2 is a graph showing the longitudinal distribution of the spherical aberration of the spherical aberration of the visible light (wavelength 400-700 nm) of the optical lens in the first embodiment of the present invention. It can be seen from FIG. 2 that the longitudinal spherical aberration of the optical lens imaging visible light in the first embodiment of the present invention is controlled to be between -0.02 and 0.02 mm in the longitudinal distribution.

Further, FIG. 3 is a horizontal distribution curve diagram of chromatic aberration of visible light imaging of the optical lens according to the first embodiment of the present invention. It can be seen from FIG. 3 that the lateral chromatic aberration is controlled between -3 and 3 μm.

Further, FIG. 4 shows curve curves of imaging field curvature characteristics of the optical lens to visible light in the first embodiment of the present invention. Wherein, the curves T and S are the characteristic curve of tangential field curvature and the characteristic curve of sagittal field curvature, respectively. It can be seen from FIG. 4 that the meridional field curvature value and sagittal field curvature value of the optical lens in the first embodiment of the present invention are controlled within a range of -0.04 to 0.04 mm.

Further, FIG. 5 shows a distortion characteristic curve diagram of the optical lens imaging visible light in the first embodiment of the present invention. It can be seen that the distortion of the optical lens in the first embodiment of the present invention is controlled within -10%~0.

Second embodiment

The following Tables 3-4 respectively show some parameters of the optical lens in the second embodiment of the present invention. In Table 1, where R represents the radius of curvature of the corresponding surface, L represents the separation distance between two adjacent surfaces on the optical axis 110, N represents the refractive index of each surface, Vd represents the Abbe number, and K represents the conic constant .

The values in Table 3-4 also satisfy the above formula (a), so that the first lens element 10, the second lens element 20, and the third lens element 30 in the optical lens 100 in the second embodiment of the present invention can be obtained , The fourth lens element 40, the fifth lens element 50 and the sixth lens element 60 correspond to the first surface 101, the second surface 102, the third surface 201, the fourth surface 202, the fifth surface 301, the third The six surfaces 302, the seventh surface 401, the eighth surface 402, the ninth surface 501, the tenth surface 502, the eleventh surface 601, and the twelfth surface 602 are aspherical.

Further, further, according to the data in Table 3-4, the optical lens according to the second embodiment of the present invention satisfies the following relationship: EFL=0.73; F=2.4; 2ω=94.9°; TTL=3.46; IMH=1.71; T45=0.02; T45M=0.05; N4/N5=1.06; V4/V5=0.40; f1/(f4*f5)=1.37; D1/(R1*R2)=2.64.

Further, referring to FIGS. 6-9, the optical lens in the second embodiment of the present invention shows the spherical aberration in the longitudinal distribution characteristic curve, the imaging chromatic aberration in the horizontal distribution characteristic curve, and the imaging field curvature characteristic Curve graph and distortion characteristic curve graph.

It can be seen from FIG. 6 that the longitudinal spherical aberration value generated by the optical lens imaging visible light in the second embodiment of the present invention is controlled within the range of -0.01 mm to 0.01 mm in the longitudinal distribution.

It can be seen from FIG. 7 that the lateral distribution of the chromatic aberration generated by the optical lens imaging visible light in the second embodiment of the present invention is controlled to be between −4 and 4 μm.

It can be seen from FIG. 8 that the meridional field curvature value and sagittal field curvature value of the optical lens in the second embodiment of the present invention are controlled within a range of -0.02 mm to 0.04 mm.

It can be seen from FIG. 9 that the distortion of the optical lens 100 in the second embodiment of the present invention is controlled within 0-8%.

In summary, all of the optical lenses in the embodiments of the present invention achieve the reduction in the overall size of the optical lens while improving the imaging quality through the above-mentioned relational expressions (1)-(9).

Understandably, for those of ordinary skill in the art, various other corresponding changes and modifications can be made according to the technical concept of the present invention, and all these changes and modifications should fall within the protection scope of the claims of the present invention.

10: First lens element

101: first surface

102: second surface

20: Second lens element

201: third surface

202: fourth surface

30: third lens element

301: Fifth surface

302: Sixth surface

40: fourth lens element

401: Seventh surface

402: Eighth surface

50: fifth lens element

501: Ninth surface

502: Tenth surface

60: sixth lens element

601: Eleventh surface

602: Twelfth surface

70: filter

80: like plane

100: optical lens

110: optical axis

120: Aperture

Claims (8)

An optical lens has an optical axis. The optical lens includes a first lens element, a second lens element, a third lens element, and a fourth lens element arranged in this order from the object side toward the image side along the optical axis. A fifth lens element, a sixth lens element and an image plane, the first lens element has a first surface and a second surface, the second lens element has a third surface and a fourth surface, and the third lens element has Fifth and sixth surfaces, the fourth lens element has a seventh surface and an eighth surface, the fifth lens element has a ninth surface and a tenth surface, and the sixth lens element has an eleventh surface and The twelfth surface also includes an aperture located on the optical axis and disposed between the second lens element and the third lens element. The improvement is that the optical lens satisfies the following relationship: 0< T45<0.1; 0<T45M<0.2; 0.77<f1/(f4*f5)<2.75; where T45 is the level between the center of the eighth surface to the intersection of the ninth surface and the optical axis Distance, T45M is the maximum value of the horizontal distance between the eighth surface and the ninth surface, f1 is the focal length of the first lens element, f4 is the focal length of the fourth lens element, and f5 is the The focal length of the fifth lens element. The optical lens as described in item 1 of the patent application scope, which further includes a filter disposed between the sixth lens element and the image plane and spaced apart, the filter having a front surface and Said the front surface opposite the back surface. The optical lens as described in Item 1 of the patent application range, wherein: the first surface is a convex curved surface protruding toward the object side, the middle of the second surface is a concave curved surface toward the image side, and the periphery of the second surface A flat surface, the third surface is a concave curved surface toward the object side, the fourth surface is a convex curved surface toward the image side, the fifth surface is a convex curved surface toward the object side, and the sixth surface is toward the image side Square convex surface, the seventh surface is a concave curved surface toward the object side, the eighth surface is a concave curved surface toward the image side, the edge of the ninth surface is a plane, and the middle of the ninth surface is toward the object side A convex curved surface, the tenth surface is a convex curved surface toward the image side, the eleventh surface is a concave curved surface toward the object side, and the middle of the twelfth surface is a concave curved surface toward the image side. The optical lens according to item 1 of the patent application scope, wherein: the first lens element, the fourth lens element, and the sixth lens element all have negative refractive power, and the second lens element, the third lens element And the fifth lens element has a positive refractive power. The optical lens as described in item 2 of the patent application scope, wherein the optical lens further satisfies the following relationships: 1.02<N4/N5<1.58, 0.28<V4/V5<0.85, where N4 and N5 are the fourth The refractive index of the lens element and the fifth lens element, V4 and V5 are Abbe numbers of the fourth lens element and the fifth lens element, respectively. The optical lens as described in item 2 of the patent application scope, wherein the optical lens further satisfies the following relationship: 1.12<TTL/IMH<3.05, 90°<2ω<150°, where TTL is the first lens element’s The horizontal distance between the first surface and the image plane, IMH is the diameter of the largest imaging circle of the optical lens, and ω is the half angle of view. The optical lens as described in Item 2 of the patent application range, wherein the optical lens further satisfies the following relationship: 0.35<D1/(R1*R2)<16.31, where D1 is the aperture of the first lens element and R1 is The radius of curvature of the first surface, R2 is the radius of curvature of the second surface. The optical lens according to item 2 of the patent application scope, wherein: the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element are all The optical axis is arranged axisymmetrically.

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